Insteon is still X-10. While X-10 transmits it's signals via PLC's, the Insteon line transmits both PLC and RF signals at the same time for more reliable operation. The Insteon devices also act as repeaters, so theoretically the more of them you install on the system, the better the reliability of the whole system. I have not tried Insteon yet, the X-10 stuff is expensive enough!
